How to get more that 20 doc in set_query?

I’m using set_query on a link field to get docs from a doctype. But it is limited to 20 docs. How can I get more (remove the limit)?

In we can do this by adding 'limit_page_length': 34 to the args. How to do it with set_query?

Thank you

frm.set_query("item", () => {
	return {
		filters: {
			is_stock_item: 1,
		page_length: 3,